Website:http://biz.LGservice.com E-mail:http://www.LGEservice.com/techsup.html COLOR MONITOR SERVICE MANUAL CHASSIS NO. : CA-103 FACTORY MODEL: FB795E MODEL: ) 795FT Plus (FB795E-UA), 795FT Plus (FB795E-UP) ) ID LABEL Model No. CAUTION BEFORE SERVICING THE UNIT, READ THE SAFETY PRECAUTIONS IN THIS MANUAL.
26kV. The following steps describe modify the original design without obtaining written how to measure the high voltage and how to prevent X- permission from LG or you will void the original parts and radiation. labor guarantee.
TIMING CHART VIDEO SYNC FACTORY PRESET MODE MODE MARK MODE 1 MODE 2 MODE 3 MODE 4 VESA Sync Polarity – Frequency 43.269 53.674 68.677 91.146 µs Total Period 23.112 18.631 14.561 10.971 µs Video Active Time 17.778 14.222 10.836 8.127 µs Blanking Time...
OPERATING INSTRUCTIONS FRONT VIEW REAR VIEW AC Power Socket USB Downstream ports See Front Control Panel Power Button D-Sub Signal Connector USB Upstream port Front Control Panel 1. Power ON/OFF Button 4. OSD Select/adjust Button This button is used to turn the monitor ON and Use these button to choose or adjust items in the OFF.
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Universal Serial Bus Making use of USB (Universal Serial Bus)* USB(Universal Serial Bus) is an innovation in connecting your different desktop peripherals conveniently to your computer. By using the USB, you will be able to connect your mouse, keyboard, printer, and other peripherals to your monitor instead of having to connect them to your computer.
DISASSEMBLY 1. TILT/SWIVEL REMOVAL 1) Set the monitor face downward. 2) Pressing the latch (a), carefully remove the Tilt/Swivel by pulling it upward. 2. BACK COVER REMOVAL 1) Remove four screws (a) from the Back Cover. 2) Slide the Back Cover away from the Front Cabinet of the monitor.
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4. TOTAL CHASSIS ASSEMBLY REMOVAL 1) Disconnector the CDT Earth Pin(a). 2) Remove four screws (a). 3) Disconnect P901 (Degaussing pin), P701 (DY pin), P451, P453 from the Main PCB. 4) Disconnect P301, P302, P303 from the Video PCB. 5) Remove the DY Assembly Screw (c). 6) Carefully separate the CDT Board Assembly from the CDT neck.
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6. MAIN BRACKET & CONTROL PCB ASS’Y 5. BOTTOM BRACKET REMOVAL REMOVAL 1) Remove five screws (a). 1) Remove eight screws (a). 2) Remove the Bottom Bracket. 2) Carefully remove the Metal Rear Shield from the Main PCB Board. 3) Removethe screw (b). 4) Remove the Control PCB Assembly from the Main Bracket.
DESCRIPTION OF BLOCK DIAGRAM 1. Line Filter & Associated Circuit. 5. X-ray Protection. This is used for suppressing noise of power input line This circuit detects the rectified DC voltage comes flowing into the monitor and/or some noise generated from the FBT pin 4. If the high voltage of the FBT in this monitor flowing out through the power input reaches up to about 30kV (abnormal state), H.V control (IC702) detects.
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11. D/D Drive & Convert Circuit. 19. Image Rotation (Tilt) Circuit. This circuit is used for supplying B + voltage to This circuit corrects the tilt of the screen by supplying horizontal deflection output transistor (Q708). This the image rotation signal to the tilt coil which is circuit makes to add side-pincushion correcting signal attached to the CDT near the deflection.
ADJUSTMENT GENERAL INFORMATION All adjustment are thoroughly checked and corrected 3) EEPROM ALL CLEAR Y(Yes) command. when the monitor leaves the factory, but sometimes <Caution> Do not run this procedure unless the several adjustments may be required. EEPROM is changed. All data in EEPROM (mode Adjustment should be following procedure and after data and color data) will be erased.
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11) Display color 15,0 box pattern(70x70mm) at mode 4. 6. Adjustment for Focus. 12) DRIVE ADJ command. 1) Display H character in full screen at Mode 4. 13) Set B-DRIVE to 100(decimal) at DRIVE of the 2) Adjust two Focus control on the FBT that focus alignment program.
TROUBLESHOOTING GUIDE 1. NO POWER NO POWER (POWER INDICATOR OFF) CHECK TROUBLE IN FUSE OK? FUSE (F901) CHECK TROUBLE IN D901 BRIDGE DIODE BRIDGE DIODE? (D901) CHECK C907(+) VOLTAGE TROUBLE IN 155VDC at 110V input IC901 310VDC at 220V input CHECK TROUBLE IN D912, D928 ?
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2. NO CHARACTER NO CHARACTER TROUBLE IN CHECK P301, SIGNAL CABLE, IC302 PIN 5, 6, 7 ? PC SIGNAL CHECK TROUBLE IN IC302 PIN 18, 19, 20, IC302, P302 PIN 6 (5V) ? CHECK IC303 PIN 1, 3, 5 TROUBLE IN PIN10 (12V), IC303 PIN 6 (80V) ?
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3. NO RASTER NO VIDEO (POWER INDICATOR GREEN or AMBER) CHECK AMBER POWER INDICATOR TROUBLE IN GREEN or AMBER ? P302 SIGNAL CABLE GREEN MIN. ROTATE SCREEN CHECK (Counter-clockwise) CONTROL KNOB TO SCREEN CONTROL CLOCKWISE KNOB OF FBT CHECK VOLTAGE AT D912 CATHODE (190V) TROUBLE IN PRIMARY D928 CATHODE (80V)
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4. NO VERTICAL DEFLECTION NO V-DEFLECTION (ONE HORIZONTAL LINE) CHECK TROUBLE IN IC601 Pin 2 T901 PIN 15 (15V) ? CHECK TROUBLE IN IC601 PIN 4 T901 PIN 17, D906 (-12V)? CHECK TROUBLE IN IC701 PIN 13 IC701 (SAWTOOTH WAVE)? TROUBLE IN IC601, V-CIRCUIT - 20 -...
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5. TROUBLE IN DPM STAND-BY/SUSPEND/ OFF MODE FAILURE CHECK CHECK PC, IC401 (MICOM) NO H / V SYNC SIGNAL (PC IS NOT GOING INTO PIN 40, 41 (H/V INPUT) DPM MODE) SIGNAL? INPUT H/V SYNC CHECK TROUBLE IN IC401 PIN 9, 8 X401, IC401 WAVEFORM? CHECK...
6. NO DEGAUSSING NO DEGAUSSING CHECK TROUBLE IN IC401 PIN 6 IC401 (MICOM) (5V)? CHECK TROUBLE IN Q908 COLLECTOR D914 VOLTAGE (0.5V)? CHECK TROUBLE IN P901? P901 CHECK TROUBLE IN RL901? RL901 TROUBLE IN TH901, DEGAUSSING COIL - 22 -...
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7. TROUBLE IN OSD NO OSD CHECK TROUBLE IN IC301 PIN 4 P302 (5V) ? CHECK IC301 PIN 5 TROUBLE IN (NEGATIVE H-PULSE P302 COMES IN ?) CHECK IC301 PIN 18 TROUBLE IN (V-PULSE COMES IN?) P302 CHECK IC301 PIN 13, 14, 15 TROUBLE IN (IS THERE ANY SIGNAL IC301, IC401...
REPLACEMENT PARTS LIST CAUTION: BEFORE REPLACING ANY OF THESE COMPONENTS, READ CAREFULLY THE SAFETY PRECAUTIONS IN THIS MANUAL. * NOTE SAFETY Mark AL ALTERNATIVE PARTS MODEL: (FB795E-UA), (FB795E-UP) DATE: 2001. 8. 24. MODEL: (FB795E-UA), (FB795E-UP) DATE: 2001. 8. 24. *S *AL LOC. NO. PART NO.
PIN CONFIGURATION M24C08 Serial I C BUS EEPROM SYMBOL DESCRIPTION PSDIP8 (BN) 0.25mm Frame E0-E2 Chip Enable Input Serial Data Address Input/Output Serial Clock Write Control SO8 (MN) 150mil Width Supply Voltage TSSOP8 (DW) Logic Dirgram Ground 169mil Width HEF4013B Dual D Flip-Flop BLOCK DIAGRAM HEF4013B...
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STR-F6454R(LF1351)5P BK SWITCHING REGULAATOR POWER BLOCK DIAGRAM START O.V.P LATCH DRIVE T.S.D SENSE O.S.C CONST ERROR 1 2 3 4 5 Terminal Symbols Description Functions Input of overcurrent detection signal and O.C.P/F.B Overcurrent/Feedback terminal constant voltage control signal Source terminal MOS FET source Drain terminal MOS FET drain...
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TYPE PARTS TYPE PARTS IRFS630A 2N3904 IRFS640A KSB564AC KTA1275 KTC3206 KTC3207 KTA1270 DTC114E KTC3198 KTC3202 KTC200-Y 1: GND 2: OUT 3: IN - 38 -...